Recently, in the treatment of acute myocardial infarction and angina pectoris, percutaneous coronary intervention (percutaneous transluminal coronary angioplasty) has been performed such that blood flow is improved by widening a lesion (stenosed portion) of the coronary artery with a balloon catheter (for example, refer to JP-T-2008-501408). Treatment using a balloon catheter has also been performed so as to improve a lesion formed inside other blood vessels, the bile duct, the trachea, the esophagus, the urethra, and other body lumens.
Generally, a balloon catheter is configured to include a long shaft, and a balloon which is provided on the distal side of the shaft and inflates in the radial direction. The balloon catheter is delivered to a stenosed portion in a body after a preceding guide wire is inserted through. In a state where the balloon is disposed at the target stenosed portion, the balloon is inflated by pressure-feeding an inflation fluid into the balloon, and thus, the stenosed portion can be widened.
In order to effectively treat a lesion, the balloon used in the balloon catheter is required to have sufficient strength so as to have a desired balloon shape when being maximally inflated, and to widen the lesion. Therefore, in order to apply high-pressure resistance, low compliance properties, and the like to a balloon, it is known to have a net-shaped reinforcement member in a wall forming the balloon (for example, refer to JP-T-2008-501408).
A balloon catheter can be used to transport a balloon to a lesion inside a body lumen. Since the balloon needs to pass through the inside of the bent body lumen while being transported, the balloon is required to have flexibility so as to follow the bending of the body lumen. However, the technology in the known art, in which a reinforcement member is provided in a wall forming a balloon, is problematic in that the reinforcement member is integrally fixed to the balloon and the degree of freedom of movement with respect to the wall of the balloon is restricted. Hence, it is difficult to achieve sufficient flexibility in the balloon.